1. Field of the Invention
This invention relates to a process and system for refilling printer ink cartridges.
2. Background Art
Inkjet printers have gained popularity among computer users in view of their low initial cost and versatility. They also produce letter and graphic prints with high quality. The ink required by printing is provided by ink cartridges mounted to the print head of the printer. Ink is held in a carrier material such as foam fiber located within a cartridge, which is saturated with the ink. The printer extracts the ink from the cartridge by vacuum pressure and delivers it to the print head. Inkjet printers consume printing ink at a fast rate particularly when printing graphics and photographic pictures. As an ink cartridge only holds a limited amount of ink, the cartridges would require replacing frequently. Therefore, the cost of operating an inkjet printer is high with the necessity of having to replace the ink cartridges frequently. Furthermore, the spent cartridges are discarded in the garbage which contributes to the contamination of the natural environment. In order to alleviate the above problems, the users of inkjet printers seek to refill the consumed cartridges rather than replacing them with new cartridges so as to reduce the operating cost as well as the unnecessary discarding of the used cartridges. However, when the printer can no longer extract ink from an ink cartridge, there is actually still a trace of ink remaining within the cartridge. Such small amount of ink remnant would quickly become dry up to blockage at the cartridge nozzle and hardening of the carrier material particularly adjacent to the nozzle. When fresh ink is injected into the cartridge for refilling it under such condition, the harden carrier material would loose the required physical characteristic for holding the ink and delivering it to the print head under vacuum. Furthermore, the dry up remnant of ink at the nozzle also form blockage to impede the flow of ink out of the cartridge.
For the above reason, it has been problematic in the refilling of ink cartridges in that the nozzle of the cartridge without resolving the above problems. The blockage at the nozzle may be removed by cleaning the nozzle external surface with water if the cartridge is to be refilled as soon as the ink has been consumed. However, cleaning the nozzle externally often does not eliminate the blockage within the opening of the nozzle particularly when the cartridge has been removed from the printer for some time without refill it immediately. Also, it does not eliminate the hardening of the carrier material in the cartridge. Thus, the refilled cartridge either does not function or will only function inefficiently. Furthermore, the wiping operation would often destroy the physical structure of the nozzle.
Attempts have been made to remove the internal ink remnant from the cartridge by injecting hot water into the cartridge through the nozzle. However, since the openings of the nozzle of the cartridge are very small, such process is rather messy and unsatisfactory as very little amount of hot water would penetrate into the cartridge.